Market demand is

The correct answer is: A. the sum of all individual demands.

Market demand is the total demand for a good or service by all consumers in a given market. It is calculated by adding up the individual demands of all consumers in the market.

Individual demand is the amount of a good or service that a consumer is willing and able to purchase at different prices. It is determined by the consumer’s income, preferences, and the prices of other goods and services.

Market demand is important because it helps businesses to determine how much of a good or service to produce. It also helps businesses to set prices for their products.

Here is a brief explanation of each option:

• Option B: demand at prevailing average prices. This is not the definition of market demand. Market demand is the total demand for a good or service by all consumers in a given market, not the demand at a particular price.
• Option C: ability to pay the price asked. This is also not the definition of market demand. Market demand is the total demand for a good or service by all consumers in a given market, not the ability of consumers to pay the price asked.
• Option D: demand in a perfectly free market. This is not the definition of market demand. Market demand is the total demand for a good or service by all consumers in a given market, not the demand in a perfectly free market.